[svn] added groupby filter and fixed some small bugs

--HG--
branch : trunk
diff --git a/CHANGES b/CHANGES
index fca9a18..6bf0278 100644
--- a/CHANGES
+++ b/CHANGES
@@ -12,6 +12,8 @@
 
 - once again improved debugger.
 
+- added `groupby` filter.
+
 
 Version 1.1
 -----------